BELT FRICTION

1
BELT FRICTION

• 1. How does T vary around drum?
• 2. How are T1, T2 related at impending slip?

Assume belt slips right T2gtT1.
2
Belt Element Free Body

• Impending slip ?F ms ?N

3
Equilibrium

• ?Fx0 ?
• (T?T) cos?q/2 - Tcos?q/2 - ?F 0
• ?Fy0 ?
• -(T?T) sin?q/2 - Tsin?q/2 ?N 0
• ?F ms ?N

4
Governing Equation

• ?T cos?q/2 - ms(2T?T) sin?q/2 0
• ?T - ms(2T?T) ?q/2 ? 0
• Governing differential equation

5
Solution

• Differential equation
• Initial condition T(q0) T1
• Integrate

6
more

• Recall
• Integration
• Solution

b in radians!
7
Discussion

• Relate T2 to T1 for the following configurations.
  

b p
b 5p
b 3p